Interaction of the HIV-1 rev cofactor eukaryotic initiation factor 5A with ribosomal protein L5.
It has previously been shown that interaction of eukaryotic initiation factor 5A (eIF-5A) with the Rev trans-activator protein of HIV-1 mediates the transport of unspliced or incompletely spliced viral mRNAs across the nuclear envelope. Consequently, mutants of eIF-5A block Rev function and thereby replication of HIV-1 in trans, indicating that eIF-5A is a crucial protein that connects the viral Rev regulator with cellular RNA transport systems. Here we show that the ribosomal protein L5, which is the central protein component of the 5S rRNA export system, is a cellular interaction partner of eIF-5A. Functional studies demonstrate that overexpression of L5 protein significantly enhances Rev activity. Furthermore, Rev nuclear export activity is inhibited in human somatic cells by antibodies that recognize eIF-5A or L5. Our data suggest that the Rev export pathway shares components of a cellular transport system involved in the intracellular trafficking of polymerase III (5S rRNA) transcripts.
Schatz
O
O
Medical Policlinic, Pettenkoferstr. 8a, D-80336 Munich, Germany.
Oft
M
M
Dascher
C
C
Schebesta
M
M
Rosorius
O
O
Jaksche
H
H
Dobrovnik
M
M
Bevec
D
D
Hauber
J
J
D000595:Amino Acid Sequence; D001692:Biological Transport; D002467:Cell Nucleus / Q000378:metabolism; D015967:Gene Expression Regulation, Viral; D015694:Gene Products, rev / Q000378:metabolism*; D015497:HIV-1 / Q000235:genetics*; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D010448:Peptide Initiation Factors / Q000378:metabolism*; D011485:Protein Binding; D012367:RNA, Viral / Q000378:metabolism*; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae; D016415:Sequence Alignment; D054321:rev Gene Products, Human Immunodeficiency Virus; D000097574:Eukaryotic Translation Initiation Factor 5A
D015694:Gene Products, rev; D010448:Peptide Initiation Factors; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D011994:Recombinant Proteins; D012269:Ribosomal Proteins; D054321:rev Gene Products, Human Immunodeficiency Virus; D000097574:Eukaryotic Translation Initiation Factor 5A; C029742:ribosomal protein L5